The work proposed in this grant is part of a research program directed at understanding the control of movement. One of our most common and vital actions is to reach out and grasp an object. It is a complicated task involving the integration of sensory information with motor control of the entire limb, yet under normal circumstances we perform the task effortlessly. I believe that the cerebellum plays a major role in integrating and generating motor commands to achieve such control, and this proposal combines behavioral, physiological and anatomical techniques to understand cerebellar action. Specifically I will relate neural discharge to parameters of coordinated movements. The results of these studies will help unravel the control codes (or motor "language") that the nervous system uses to make movements. I will also use modern anatomical techniques to specifically relate neural structures involved in motor control. By discovering interrelated elements of the nervous system we will be able to trace information flow through the nervous system as sensory input is converted to motor output. Understanding processing occurring in the cerebellum will be a major scientific advancement. The information gained will be of help to scientists attempting to understand and correct pathological states affecting our control movement. Our attempts to return disabled people to an active life are in their infancy. Even small advances in our knowledge could be large advances in their lives.